Within the spine, the intervertebral disc functions to stabilize and distribute forces between vertebral bodies. The intervertebral disc comprises a nucleus pulposus which is surrounded and confined by the annulus fibrosis. Intervertebral discs are prone to injury and degeneration. For example, herniated discs typically occur when normal wear, or exceptional strain, causes a disc to rupture. Degenerative disc disease typically results from the normal aging process, in which the tissue gradually loses its natural water and elasticity, causing the degenerated disc to shrink and possibly rupture.
Intervertebral disc injuries and degeneration are frequently treated by replacing or augmenting the existing disc material. Current methods and instrumentation used for treating the disc require a relatively large hole to be cut in the disc annulus to allow introduction of the implant. After the implantation, the large hole in the annulus must be plugged, sewn closed, blocked or otherwise repaired to avoid allowing the implant to be expelled from the disc. Besides weakening the annular tissue, creation of the large opening and the subsequent repair adds surgical time and cost. Further, many disc augmentation procedures require a discography or other imaging of the patient's intervertebral disc prior to the augmentation procedure. In that regard, the discography typically involves introducing a contrast media into the intervertebral disc space. It takes several hours or even days for the contrast media to diffuse out of the intervertebral disc and for the intradiscal pressure to go back to the level present before the discography. Accordingly, a need exists for improved methods, systems, and apparatus for treating an intervertebral disc using minimally invasive surgical techniques.